The invention relates to a method of manufacturing a plain bearing for a movable functional part which is formed integrally with its bearing part at a metal bearing plate by a synthetic-resin injection moulding technique, such as the outsert moulding technique. More particularly, the invention relates to functional parts which are formed by this technique with a bearing bridge extending through a hole of the metal bearing plate, which hole has hole walls, and bears on both plate surfaces laterally of the hole with retaining pieces, after which the bearing part comprising the bearing bridge and the retaining pieces is changed by a deformation process following the injection moulding process in such a manner that it forms a rotation or slide bearing together with the bearing plate. The invention also relates to a device for carrying out this method, and to a bearing part of the plain bearing of the movable functional part. The plain bearing is provided in particular for forming rotational or slidable parts with plain bearing quality on metal plates in running gears of tape reproduction devices, the parts being moulded at the metal plates by the outsert moulding technique.
Such a method of manufacturing a bearing of a movable functional part is known from EP 392 600 A2. The bearing plate in that case is a base plate which is provided with a plurality of retaining, supporting and functional parts, the parts provided by injection or moulding each gripping the plate by means of a bridge extending through a plate hole and retaining pieces provided on either side of the plate surfaces. Such parts are either fixed or have a limited rotation capability; they exhibit no bearing properties.
EP 392 600 A2 describes that the movable bearing part comprising the bridge and the retaining pieces provided on either side of the plate surfaces can be so changed by a subsequent deformation operation that the bearing is made into a plain bearing. Slides, wheel bearings for slides and gearwheels, for example, can be formed in this manner directly at the metal plate.
Reference is made in this connection to U.S. Pat. No. 3,214,504, which discloses how synthetic-resin injection-moulded spindle ends are made capable of rotation by a flexing operation in the manufacture of a spindle for a fishing rod.
DE-AS 14 72 403 discloses a method of manufacturing a mitre gear drive from synthetic-resin gears according to which the mitre gear bearings are formed in that the gear spindles are injected through a hole in a retaining plate and a wide overlap of the spindle hole, through which injection took place, is effected at the mitre gear side, while the overlap at the other side of the retaining plate is only small. The mitre gear wheels are brought into mutual engagement in that the retaining plate is crimped over. The crimping operation at the same time achieves a locking of the mitre gear wheels against dropping out. It is not described in what manner the injected parts obtain bearing properties.